A low fire-spreading wrapping paper used for cigarettes has lately grown popular. This low fire-spreading wrapping paper prevents fire from spreading to a combustible material in the event that a lighted cigarette using the wrapping paper is dropped on the combustible material. The cigarette includes smoking material such as shred tobacco, and paper wrapping the smoking material. This paper is the low fire-spreading wrapping paper (for example, see FIG. 2 of Patent Document 1).
More specifically, the low fire-spreading wrapping paper disclosed in Patent Document 1 includes a paper web and bands that are longitudinally arranged in the web at predetermined intervals. These bands are formed by applying a combustion inhibitor onto the web. The combustion inhibitor is generally applied as an aqueous solution. The web applied with the combustion inhibitor is dried by a dryer to be formed into a low fire-spreading wrapping paper.
After being dried, the wrapping paper is reduced in width as a result of drying shrinkage by about 3 percent to about 7 percent. For example, if the original width of the wrapping paper is 1040 mm, the paper width will become 1010 mm at a shrinkage rate of 3 percent, and 970 mm at a shrinkage rate of 7 percent. The dried web is provided with slits of 27 mm wide, and is wound into rolls as wrapping papers each having a width of 27 mm. While the wrapping paper dried at a 3 percent shrinkage rate can make 37 rolls of 27 mm slits, the one dried at a 7 percent shrinkage rate makes 35 rolls. In this way, the different shrinkage rates produce different numbers of wrapping paper rolls, which destabilizes the manufacture. Moreover, because the combustion inhibitor applied onto the web are fixed in amount and application intervals, if the number of the produced rolls is different from wrapping paper to wrapping paper, the application amount of the combustion inhibitor is also unequal from roll to roll. This results in a failure of producing wrapping papers of the stable quality.
In order to maintain a constant shrinkage rate, drying temperature and web tension are controlled. However, it is necessary to change the temperature setting with the seasons, and also from morning to afternoon. It is thus troublesome to maintain the constant shrinkage rate.